1. Field of the Invention
The present invention relates to a facial image information conversion method and facial image information conversion apparatus for generating facial image information with a specified facial expression on the basis of facial image information taken with respect to a certain person.
2. Description of the Background Art
It is said that facial expression which is one information of emotion has a great role in transmitting information in the communication between human beings. It is therefore important to carry out analysis and composition of a facial expression of a person in information transmission such as a teleconferencing system and the like.
In a conventional facial expression generation technique, a three-dimensional configuration model is generated. The configuration is deformed to the configuration of a desired facial expression using a FACS (Facial Action Coding System) model. Then, a picture of a face obtained by a three-dimensional scanner is pasted on the wire frame model in compliance with the deformation to generate a facial expression. A computer of high performance dedicated to image processing is required in order to generate and deform a three-dimensional configuration model. Also, a three-dimensional scanner device is required to generate a facial expression. Furthermore, knowledge of a high level is required to develop an appropriate program. It was not easy to implement such a system. There was also a disadvantage in that the generated facial expression lacks realistic reproduction of wrinkles in the face in accordance with change in the facial expression.
In order to overcome such problems, there is an approach of realizing a desired facial expression by replacing characteristic portions of a face such as the mouth and eyes with the characteristic portions of another person with a desired facial expression. However, this approach has the disadvantage that it is difficult to recognize that the facial expression belongs to a certain person when the constituent portion of the face that are not those of the person himself/herself increases.
There is also a method of realizing a desired facial expression by deforming and replacing such characteristic portions with those of-a desired facial expression of the same person. However, there was a problem that the facial expression is not natural since the entire face is not deformed in this method.